Portable pneumatic stapling machine



H. D. RANDALL PORTABLE PNEUMATIC STAPLING MACHINE Dec. 12, 1933.

Fil ed Nov; 1, 1952 3 Sheets-Sheet 1 Dec. 12, 1933. H. D. RANDALL 1,

PORTABLE PNEUMATIC STAPLING MACHINE Dec. 12, 1933. H. D. RANDALL PORTABLE PNEUMATIC STAPLING MACHINE Filed Nov. 1. 1932 3 Shegts-Sheet 3 Patented Dec. 12, 1933 PORTABLE Howard D. Randall,

mmm s'mrnme MACHINE Cincinnati, Ohio, assignor to The Randall Company, Cincinnati, Ohio, a cornation of Ohio Application November l, 1932. serial No. 640,639

20 Claims.

This invention relates to a portable pneumatic stapling device of pistol-like form, wherein the parts are so compact and simplified in every way as to enable an eflicient device to be made weighing substantially 3 pounds. It is capable of being operated readily by one hand and applied to all sorts and conditions of use, whether for upholstering on the interior of motor cars or upon exterior surfaces, all manual operations of feeding, forming, cutting and driving being eliminated. It is also designed to be used in stapling moldings having an elongated narrow opening or groove for the insertion of concealed staples or tacks, and the various parts are especially designed for that particular use.

, The objectionable vibration incident to most pneumatic devices has been eliminated, the machine being designed to be of the single piston and single stroke type such that upon depressing the trigger of the pistol one staple will be driven and the parts automatically retracted to position ready for another driving operation upon again depressing the trigger, the said piston being retracted when the trigger is released. If the trigger is not released, the machine will merely remain inoperative after the staple is driven, and a depression of the trigger for an interval will be sufiicient to cause one complete operation of the machine.

The aim of the invention is to reduce the weight of this stapling machine without impairing, in any way, its efliciency. For one thing, the size of the pneumatic cylinder has been reduced to the limit in order to keep down the weight of 0 the device, but the desirable impact blow of the driver operated by the piston of the pneumatic cylinder has been attained by auxiliary mechanism of such character as to give a quick release to the valve for the cylinder inlet, causing the air to be applied in an improved manner.

In the effort to simplify the device and reduce the weight of the parts, a staple strip of substantially the kind described in my co-pending application, Serial No. 631,411 is employed and this stapling device is designed to have a strip of one hundred staples capable of being fed through the handle of the machine or transversely to the same, it being obvious that in certain kinds of application it will be desirable to have the strip of staples fed through the handle. In case a reel of staples is used, the machine may be given a capacity of 1000 staples, if a strip of 4 inch diameter is used.

One general aim of the invention has been to depend upon a single forming, cutting and driving member directly applied to its various operations by means of air pressure of such character that it will lessen the weight and cooperate properly with the nozzle. During some part of the forming and driving operation an auxiliary device is put under tension by air pressure, so that this auxiliary device will advance the strip of staples thereby positioning one staple in the path of the driver after it has been retracted, said staple being then ready to be driven upon a subsequent depression of the trigger.

In order to utilize the foregoing principle of operation, it is necessary to provide feeding mechanism for the strip of staples, whether nested or arranged in one long strip, of such character as to insure the strips being advanced with the minimum of friction and to protect the strip and the severed staple against rearward displacement caused by the cutting operation. The strip of staples has been designed to permit the use of a support having therein dogs arranged to prevent this backward movement and the forward end of the support also forms a stop for the severed staple.

Another important feature is in the design of a floating piston to which the forming, cutting and driving member is attached, which is operated by a supplemental piston contacting against the adjacent surface of said floating piston, thereby permitting it to center itself automatically to take care of the various strains and stresses to which the cutting and driving member is necessarily subjected.

ill

By reason of the particular formation of the strip of staples, it is possible to nest a number of strips in reels, feeding them therefrom in an improved manner as fully shown and described in said co-pending application.

Other objects and advantages will be in part indicated in the following description and in part rendered apparent therefrom in connection with the annexed drawings.

To enable others skilled in the art so fully to apprehend the underlying features hereof that they may embody the same in the various ways contemplated by this invention, drawings depicting a preferred typical construction have been annexed as a part of this disclosure and, in such drawings, like characters of reference denote corresponding parts throughout all the views, of which:

In the drawings, Figure 1 is a side elevation of the machine. Fig. 2 is taken from the opposite side of the machine. Fig. 3 is a central longitudinal section taken on the line 3-3 of Fig. 6 in the direction of the arrows. Fig. 4 is a detail of a modification showing the staples fed through the handle. Fig. 5 is a side elevational view. Fig. 6 is an end view. Fig. 7 is a transverse sectional view through the nozzle and strip holder, parts being broken away. Figures 8, 9 and 10 are detail views of the nozzle applied to a molding and the molding after its application to a support. Fig. 11 is a detail view of a reel of strips of staples attached to the machine.

Referring to Figure 1, the machine is shown in the shape of a pistol gun, the handle being marked 1 and the pneumatic cylinder 2. The connection to the source of air pressure is through the pipe 3, which is shown passing through the handle in Fig. 2. The nozzle is marked 4. Within the bore of the cylinder 2 is fitted a piston plunger 5 (see Fig. 3) and an auxiliary floating plunger 6 to which is rigidly secured the forming and driving member '7. The coiled spring 8 within the bore of the cylinder bears at one end against the plunger 6 and its other end bears against the end walls of the cylinder and forms the means for retracting the member 7 after it has been advancedby the pressure of the air upon the main piston 5. There is a buffer spring also secured to said plunger 6. In this way there is disclosed a floating piston 6 which is capable of automatically centering itself to take care of the strains and stresses to which the thin, flat forming and driving member '7 will be sub jected. From the foregoing description it is apparent that compactness of parts is one of the features of the invention, which results in simplifying the construction and materially reducing the weight of the parts.

The air entering the pipe 3 is controlled by the valve 8* (Fig. 2) which is integrally formed with a valve stem 9 and plunger 10 which is reduced adjacent valve 8*. The spring 11 is positioned within a passage 12 (Fig. 3) to which the pipe 3 leads. This spring is preferably secured to the valve stem and its free end engages the seat formed in set screw 13 and thereby sufiicient tension can be applied to valve 8 to hold it on its seat until the trigger 14 is depressed by the operator. The initial movement of the trigger merely applies tension to the spring 15 and when suflicient tension has been applied by the trigger to spring 15 it will give to lug 16 a quick movement, which willbe transmitted to the plunger 10, causing a quick release of the valve against the tension of spring 11. the port 17 will be opened to the air which will pass through said port to the passage 18 which in turn connects with the rear end of cylinder 2 and in this way the air will be applied to the main piston 5.

From the port 17 there is an air passage 19 (Fig. 6) which leads to a small cylinder 20 in which is positioned the piston 21 which is formed with a rod or plunger 22. This rod at its free end engages the free end of a lever 23 hinged at 24 on the body portion of the cylinder 2. The air passages and valve are so arranged that upon the unseating of valve 8 the plunger 22 is forced upwardly by air pressure to lift the free end of said lever 23 against the tension of spring 25 which is also mounted at 26 upon said body portion of the machine. This spring 25 is preferably bifurcated (Fig. 2) and its free ends bear against the end walls of a holder 27. A lug 27 projects from said holder and lies in the path of movement of the lever 23 so that when the free end of lever 23 is raised by air pressure, the spring 25 is put under tension and the holder 27 is retracted by the engagement of the lever with lug 27 the spring 25 acting to advance the holder when the trigger 14 is released, the air pressure being thereby shut off from cylinder 20.

. There is a ratchet pawl connection between the In this wayerably one strip of 20 staples mounted on a tapered supporting block 29.

As shown in Fig. 2, this support 29 has its sides tapered outwardly and the legs of the staples are flared outwardly and are formed with tapers or bevels on their outside faces and have sharp points as fully disclosed in my pending application Serial No. 631,411. The ratchet pawl connection between the strip of staples and the holder consists of spring pressed pawls secured to the inner walls of said holder, the free ends of the pawls engaging between the staples and advancing the strip, and they are capable of sliding over the pawls upon the retracting movement of said holder in the usual and ordinary way.

The support 29 is formed with grooves in its side walls and spring pressed dogs are positioned in said grooves to prevent the strip of staples being retracted by the retracting movement of the holder or the reactionary forces due to the cutting of a staple from the strip.

As a consequence of this arrangement of parts, the strip of staples will remain in its advanced position with one staple in the path of movement of the former and driver 7 and after the staple is severed from the strip, the strip will remain immovable with its front edge engaging member '7 until the spring 25 acts to advance the strip one step, the strip being advanced only after the member 7 has been retracted sufficiently to remove that member from the path of the strip of staples.

The member '7 has its free end adapted to perform a three fold function. It is beveled as shown in Fig. 3, so that the side edges first engage the shoulders of a staple forcing the prongs or legs towards the vertical plane of the staple, the imperforate top of the staple being thereby bent to fit within the bevel or concave surface of the end of the member '7. This results in bringing the prongs of the staple within the vertical planes of the support so that when the staple is severed it will be positioned against the end wall of the support 29 which will act as a stop to prevent the staple being thrown out of position by the reactionary force incident to the cutting action. The cutting edge of the member 7 having severed the staple, the staple is free to be driven through the nozzle 4.

It will thus be seen that an anvil is dispensed with and the flat forming, cutting and driving member co-acts with the flattened nozzle 4 to initially bend the outwardly flaring prongs towards the center of the staple by the engagement with the shoulders of the staple and then sever and drive the staple through the flattened nozzle, the small pneumatic cylinder furnishing the necessary power to accomplish the foregoing results.

As shown in Fig. 3, there are guides formed within the nozzle so that the prongs first engage the tapered guides 31 and during this movement of the staple under the impelling force of the member '7, the points of the staple are forced against the side walls of said guides and bent slightly and the prongs are brought into substantially vertical or parallel position by the straight guides with the result that when the prongs penetrate wood or similar material they are brought into the clinched position indicated in Pig. 8 the outer bevel surfaces of the staple assisting to bring about this result. In driving the staples against steel or other hard material, the ends are clinched in a desirable fashion.

As shpwn in Figs. 9 and 10 the nozzle and reciprocating member '7 are so formed and shaped as to be especially adapted for use with a molding 33 having wings 34 and a groove or open space 35 between the wings 34. This groove is normally concealed by the wings which tend to close the groove, but the flat shaped nozzle is capable of being inserted within the groove, the sides of the nozzle pressing back the wings as indicated in Fig. 9. As shown most clearly in Figs. 1, 2, 5, and 9, the nozzle is provided with a flaring tip portion adapted to engage beneath the overhanging wing portions of the moulding, thereby to retain the nozzle in the channel 35 during movement of the machine along the moulding. The operator can then advance the nozzle while holding its end within the groove and by depressing the trigger will be able to drive staples at the desirable separated distances along the bottom oi the groove, the wings 34 closing the groove rearwardly of the nozzle, as it advances and relieves the wings from the pressure caused by the sides of the nozzle. In this way an effective and inexpensive molding having concealed fastenings can be quickly applied to upholstering or other articles.

The parts of this machine are easily assembled, the central casting being threaded to permit the cylinder 2 to be secured thereto. The nozzle 4 is likewise secured to the central casting by set screws 36 and the outer end of the nozzle is positioned securely in proper position by the spring pressed bolt 37 (Fig. 7).

A reel of strips, such as fully described in my pending application, may be used from which the strip can be fed transversely to the machine as shown in Fig. 5. Some of the parts are welded together, such as the nozzle which is formed in two halves and then welded.

Instead of feeding the strip of staples transversely to the horizontal plane of the cylinder 2, the strip can be fed through the handle 1, as indicated in Fig. 4, and in this modification a coiled spring 38 can be employed to exert pressure upon a conventional pusher so that upon the retraction of the member 7 the spring 38 will advance the pusher and feed the strip to proper advanced position, the staple at the free end of the strip engaging the inner wall of the central casting and, at other times, the spring will hold the free end of the strip against the reciprocating member '7. The member 7 is retracted by the spring 8 in the manner of its operation described in connection with Figure 1 and, while it is held in retracted position by the spring 8, the spring 38 causes the strip of staples to be advanced through the handle to a position such that a staple is positioned in the line of travel of said member 7 so that a staple can be cut from said strip whenever the member 7 is advanced by the compressed air against the tension of spring 8. After a staple is cut from said strip, the strip will be held against advancing movement by reason of the contact of said strip against the member 7 but so soon as spring 8 retracts said member sufficiently so that it no longer acts as a stop to the strip, then spring 38 will immediately advance the strip to the proper position.

In Fig. 11 there is shown a continuous strip of staples Wound on a support of any usual and ordinary kind of the necessary width. This reel is hinged at 39 to the stationary member 40 attached to the machine. The reel itself is clearly shown in Fig. 7 of my co-pending application. A continuous strip of preformed staples is in this manner fed to the machine. This reel may be mounted above the operator to some stationary support and by employing a flexible conduit the capacity of the machine may be increased to the desired amount.

It will thus be seen that the machine has been simplified by reducing the size and weight of the parts and by dispensing with an anvil, the staples being preformed and only requiring an initial finishing. operation by the cutting and driving member, which insures that the severed staple will be retained in proper position for the driving operation and will be driven to the best advantage. The tapered support for the strip of staples co-acts with the type of preformed strips to insure the proper feeding of the staples and guides in the nozzle will complete the formation of the staples. Upon the quick release of the valve by the depression of the spring trigger, air passes into the main cylinder and the auxiliary cylinder, thereby advancing the forming, cutting and driving iron and applying tension to the spring for feeding the staple strip so soon as the driving iron is retracted sufficiently to permit the strip to advance, the preceding staple having been finished, cut and driven.

Upon depression of the trigger the foregoing operations are performed in proper sequence and so long as the trigger is depressed the driver will remain in advanced position due to air pressure continuing to be applied to the piston, thereby making only a single stroke forward. So soon as the trigger is released and the air inlet valve closed, the staple strip will be advanced, if the driving iron has been sufficiently retracted to permit this movement. The parts are then in position for the next operation of the forming, cutting and driving iron.

In order to insure the proper operation of the retracting spring 8, the opening 41 is provided which will permit the air to be vented to relieve the piston of the main cylinder from the air pressure piling up ahead of the piston. In Figures 1, 2 and 3 an exhaust valved opening is indicated by 42 and the valve 8 is shown in Figure 3 in its normally closed position in which position valve 42 is sufficiently cracked to permit the air trapped by valve 8 to be vented. The

effect of causing the points of the staples to be turned inwardly by the guide surfaces of the nozzle, as heretofore explained, is to start the staple prongs inwardly as they enter the material to be stapled and the outer tapered surfaces on the staples co-act to cause the prongs to assume the clinched position indicated in Fig. 8. In assembling the parts of this portable and compact stapling device the flat driver memher with its encircling spring is positioned with the free end of the driver fitting within the walls of the passage formed in the nozzle. By means of a wire with a hook thereon inserted through the nozzle and engaging a spiral of the spring thereby holding the spring under tension while the free end of the driver is held within said passage until the barrel is screwed into position. The I1.-

wire can then be disengaged and removed. Other ways of assembling the parts will be obvious. In this way the end wall of the barrel holds the spring in its slightly compressed condition thereby holding the free end of the driver 3 r:

in the passageway against said initial spring tension while in its normal retracted position as indicated in Figure 3. The supplemental piston member 6 is thereby suspended free from engagement with any fixed parts and has a permissible floating movement in that it can oscillate laterally.

One main feature of my stapling machine,

which makes it adapted for use with moldings.

having narrow longitudinal grooves and similar uses, is that there are eliminated from the nozzle, which penetrates corners and narrow openings the usual anvil devices and complicated dual pistons and other devices which perform separately the functions of forming and driving.

In the invention disclosed herein there is within the nozzle a single reciprocating member of a single stroke type and stationary guide surfaces, which co-act to accomplish the final forming, cutting and driving of the staple. It is manifest that in this way the weight of the machine is reduced, the operating parts simplified and thereby the nozzle-can be shaped in a way to adapt it for corners and narrow openings.

Without further analysis, the foregoing will so fully reveal the gist of this invention that others can, by applying current knowledge, readily adapt it for various utilizations by retaining one or more of the features that, from'the standpoint of the prior art, fairly constitute essential characteristics of either the generic or specific aspects of this invention and, therefore, such adaptations shouldbe, and are intended to be, comprehended within the meaning and range of equivalency of the following claims.

Having thus revealed this invention, I claim as new and desire to secure the following combinations and elements, or equivalents thereof, by Letters Patent of the United States:

' 1. In a stapling machine having a nozzle and a pneumatic cylinder with. a two-part piston member, one part being suspended free from engagement with the walls of said cylinder and permitted to float within said cylinder, the other.

part being the main operating member and hav-v ing a loose engagement with said floating part to permit said floating member to automatically center itself within said cylinder, a forming and driving member secured to said floating part, and a substantially continuous bearing for said member extending from the cylinder to the mouth of the nozzle to permit it to reciprocate within a narrow nozzle opening.

2. In a stapling machine the combination of a pneumatic cylinder, a piston suspended within said cylinder and capable of floating free from contact with the walls of said cylinder, at flattened cutting and driving member secured to said piston, a flattened nozzle capable of receiving only said flattened driving member and the .driven staple, a driven piston cooperating with of the machine, the said member being the sole actuating means positioned within the nozzle.

4. In a stapling machine the combination of power operated feeding, cutting and driving devices, a flattened nozzle having tapered guides for forcing the prongs of the staples towards the center of the staples and forming inwardly inclined points to said staples and means on said driving device to give an initial bending operation to said prongs, the said staples having tapered outer surfaces to cause the prongs to be girawn inwardly during the flnal driving opera- 5. In a stapling machine the combination of power operated mechanism for cutting and driving preformed staples having downwardly projecting prongs, including a reciprocating driving member, a support for the preformed staples, said driving member being formed to cut and drive a staple after it is advanced beyond said support and is suspended in the path of said member and to give theprongs an initial bending operation, thereby dispensing with an anvil, and a flattened nozzle for receiving said staple and driving member having a slit-like opening, there by to position'said staple as it is driven through its narrow opening.

6. In a stapling machine power mechanism, a reciprocating member having its end capable of bending inwardly the prongs of a preformed staple, thereafter cutting the staple from its strip and finally driving it to stapled position, and a nozzle having tapering guide surfaces capable of bending the prongs of the staple into finishing the bending of said prongs to bring them into substantially parallel relation during.

their passage through the machine.

8. The method of stapling which consists in providing a preformed strip of staples with prongs flaring outwardly from the center thereof, initially bending saidprongs inwardly and cutting a staple from said strip, thereafter forming an inward bend on the point of the staple, an'd finishing the bending by forcing the staple prongs into substantial parallelism.

9. The method of stapling articles which consists in providing pre-formed staples with outwardly flaring prongs having'outer tapered surfaces, bending the prongs inwardly toward the axial center of the staples, and forming thereafter inwardly inclined portions adjacent the extremities of the prongs thereby causing the prongs to be forced into clinching position during the driving operation.

10. The method of driving staples into fabric which consists in providing strips of pre-formed staples having outwardly flaring prongs, thereafter advancing the strip over a tapered support to position one staple beyond the support, then forcing the prongs inwardly and cutting the staple from the strip, and thereafter advancing said staple while positioned against the end wall of said tapered support.

11. In a stapling machine the combination of power mechanism, a driving member, the body of the machine having a narrow slit-like opening extending therethrough capable of receiving said driving member, a support for a strip of preformed staples having their prongs bent downwardly and outwardly, mounted on said body of the machine and positioned to hold one staple suspended and unsupported by any fixed part in line with said slit-like opening, said driving member being capable of bending, cutting and driving said suspended staple, and a nozzle positioned in axial alignment with said opening and formed with a corresponding slit-like opening to receive said staple and driving member.

12. In a stapling machine the combination of a cylinder, a piston in said cylinder, a flattened reciprocating member secured to said piston, a bearing for said member projecting within said cylinder and a nozzle likewise flattened at its end, the intermediate portion of said member between said piston and said bearing being capable of being projected into said bearing and its free end projecting through an elongated opening in said nozzle, thereby forming a substantially continuous bearing for said member.

13. In a stapling machine the combination of a cylinder, a piston in said cylinder, a flattened reciprocating member secured to said piston, a bearing for said member projecting within said cylinder, and a nozzle likewise flattened at its end, the intermediate portion of said member between said piston and said bearing being capable of being projected into said bearing and its free end projecting through an elongated opening in said nozzle, the said cylinder being formed with a passage to the atmosphere to relieve the forward end of the piston from air pressure.

14. The combination in a portable compact pistol-like instrument for stapling, to a supporting member, a fabric moulding having a central elongated opening and lips projecting from its body portion normally closing said opening, means to support a strip of partially formed staples with one staple in the path of a driver, a flattened rigid nozzle, a flat strap-like driver having means for initially bending the prongs of the staple supported in the path thereof, power actuated means for operating said driver through said nozzle to drive said staple therethrough, said nozzle being capable of being inserted within said opening and being formed to open said lips and hold same open during the driving of said staple by said driver, and guides within said nozzle for supporting the driver substantially throughout its entire length during its driving operation.

15. In a portable stapling device a piston like instrument comprising a pistol grip, a cylindrical shell like container supported by said grip, a two part reduced piston occupying a minor portion of the internal bore of said container, one part fitting within the periphery of the barrel and the other part freely suspended therein, an elongated strip like member attached to said last mentioned part of the piston and bridging the major portion of internal bore of the container, pneumatic means for advancing the piston, and means for retracting same.

16. In a portable stapling device a piston like instrument having a flattened nozzle and a pistol grip, a barrel adjacent said grip, a disk like piston fitting within said barrel and a supplemental piston mounted loosely within said barrel, the two pistons occupying a minor portion of the interior of the barrel, a strip like reciprocating member attached to the supplemental piston and extending through a major portion of the interior of said barrel and capable oi! passing through said nozzle, pneumatic means for said piston, and a retracting spring extending through a major portion of said barrel.

1'7. In a portable stapling device, a hand supported instrument comprising a nozzle, a barrel, a piston in said barrel, an elongated strap-like driver positioned in said barrel and attached to said piston, pneumatic means for operating said piston, and projections on said driver for initially forming said staples and subsequently cooperating with the walls of said nozzle to further form the staple.

18. The combination in a portable pistol-like instrument for attaching a flexible moulding to a supporting member, said moulding being formed of a body portion and opposed lip portions attached to and overlying said body portion and forming between them and the body portion a longitudinal channel, of a hand grip provided with a projecting flat nozzle adapted to be placed within said channel and having a flaring tip portion adapted to engage beneath said lips to retain said nozzle in said channel during movement of said instrument along the moulding; a channel formed lengthwise of said nozzle; means to feed partially formed staples into said channel; a reciprocable plunger aligned with said channel and adapted to further form said staples and to drive them through said channel; power actuated means to operate said plunger; and trigger means to control said power actuated means.

19. A portable stapling machine combining a body portion provided with a hand grasp, a nozzle projecting from one side thereof, a channel extending through said body portion and nozzle, a cylinder supported at the opposite side of said body portion with its axis in line with said channel, means to feed staples into said channel, an actuating piston fitted within said cylinder, a guiding piston within said cylinder having one end abutting one end of said actuating piston but free to float relative thereto, a staple driving plunger having one end attached to said guiding piston and its opposite end slidingly fitted within said channel, a coil spring within said cylinder surrounding said plunger and engaging u said guiding piston to retract, as a unit, said two pistons and said plunger, and means to admit fluid pressure behind said actuating piston to advance, as a unit, said two pistons and said plunger to cause said plunger to drive a staple 2 through said channel.

20. A portable stapling machine combining a body portion provided with a hand grasp, a relatively thin and flat nozzle projecting from one side thereof, a channel extending through said body portion and nozzle, a cylinder supported at the opposite side of said body portion with its axis in alignment with said channel, means to support partially formed staples into said channel, and actuating piston and a guiding piston within said cylinder, the former being closely fitted to said cylinder and the latter being slightly smaller and adapted to have a slight floating movement relative to the former for the purpose of alignment, a combined staple-forming and staple-driving plunger of strap-like form attached to the guiding portion, said plunger having its free end formed to engage the partially formed staple at spaced points at the opposite sides of the center thereof thereby, by initial no contact, to cause the prongs oi. the partially formed staple to be deflected inwardly, means to admit fluid pressure behind said actuating piston thereby to advance said pistons and plunger to cause the latter to deflect the prongs and drive a staple, and spring means to retract said pistons and plunger.

HOWARD D. RANDALL. 

